feat(ui): use modal dialogs for entity creation and editing

Introduce reusable Modal component for forms
Update router to preserve scroll position when toggling modals
Refactor admin and entity views to render editors as overlays

frontend/src/views/RecipeDetail.vue

@@ -1,5 +1,5 @@
 <script setup lang="ts">
-import { onMounted, ref } from 'vue';
+import { computed, onMounted, ref, watch } from 'vue';
 import { useI18n } from 'vue-i18n';
 import { useRoute } from 'vue-router';
 import DetailSection from '../components/DetailSection.vue';
@@ -8,14 +8,37 @@ import EntityChips from '../components/EntityChips.vue';
 import PageHeader from '../components/PageHeader.vue';
 import Skeleton from '../components/Skeleton.vue';
 import { api, type RecipeDetail } from '../services/api';
+import RecipeEdit from './RecipeEdit.vue';
 
 const route = useRoute();
 const { t } = useI18n();
 const recipe = ref<RecipeDetail | null>(null);
+const showEditor = computed(() => route.name === 'recipe-edit');
+
+async function loadRecipeDetail() {
+  recipe.value = await api.recipeDetail(String(route.params.id));
+}
 
 onMounted(async () => {
-  recipe.value = await api.recipeDetail(String(route.params.id));
+  await loadRecipeDetail();
 });
+
+watch(
+  () => route.name,
+  (name, oldName) => {
+    if (oldName === 'recipe-edit' && name === 'recipe-detail') {
+      void loadRecipeDetail();
+    }
+  }
+);
+
+watch(
+  () => route.params.id,
+  () => {
+    recipe.value = null;
+    void loadRecipeDetail();
+  }
+);
 </script>
 
 <template>
@@ -68,4 +91,6 @@ onMounted(async () => {
       <EditHistoryPanel :entity="recipe" :history="recipe.editHistory" />
     </div>
   </section>
+
+  <RecipeEdit v-if="showEditor" />
 </template>